I purchased a brunco forced air furnace two years ago not knowing anything about burning coal.I only burned wood in a woodstove until I purchased the brunco.It was a little tricky getting the hang of burning anthracite,but once i learned how I was very impressed.The thing I overlooked buying this stove is, it is a duel fuel unit.wood or coal.I didn't know I would get hooked on burning coal.plus I really didn't know any thing about these types of furnaces.It is a pretty well built unit.Its there small one 600 lbs.I just dont like how deep the bed is.It has 9 inch high firebrick on the sides with a big cast iron rear firebrick.I was hopein to add another row of brick sideways to make my bed 4 inches deeper.The only problem I have is if I wanted to add apiece of metal angle to hold the new row of bricks in place can I drill through the fire box and just nut and bolt the metal angle or do I have to weld it in place.Ive enclosed a few pics.If anyone can help out I'd appreciate it. The top bricks in the pics are just sitting on a 1 inch steel lip.I just need to rig something to secure the top of the bricks to the side of the firebox. thanx,Joe